Stackable transport and storage container

ABSTRACT

A stackable transport and storage container molded integrally and unitarily from a synthetic resin, has a plurality of sidewalls defining corners between them. Each of the sidewalls is formed unitarily with a hinged strip which may be deflected inwardly and held in place therein by a snap-arrangement to support a similar container stacked thereon. When the strips are deflected outwardly, they allow the slightly tapered walls of the vessels to be interfitted or nested.

I 1 STACIKABLE TRANSPORT AND STORAGE CONTAINER [75] Inventor: Wilhelm Ladewig, Munich, Germany [73] Assignee: Krauss-Maffei A.G., Munich, Germany 221 Filed: June 6, 1972 [2]] Appl. No.: 260,116

[30] Foreign Application Priority Data June 9, 1971 Germany 2128547 [52] U.S. Cl. 206/506 [51] Int. Cl B65d 21/06 581 Field 1 Search 220/97 R, 97 E; 229/31 R, 1 229/010. 11; 206/506 [56] References Cited UNITED STATES PATENTS 2,868,429 1/1959 Shanahan 229/31 R 3,169,659 2/1965 I Blackmore 220/97 E 3,220,603 11/1965 Bromley 220/97 E 3,311,257 3/1967 Puerte 220/97 R 3,722,735 3/1973 Herlzer 220/97 E FOREIGN PATENTS OR APPLICATIONS 103,932 10/1963 Denmark..... 229/DIG. 11

Primary Examiner-George E. Lowrance Attorney, Agent, or Firml(arl F. Ross; Herbert Dubno [5 7] ABSTRACT A stackable transport and storage container molded integrally and unitarily from a synthetic resin, has a plurality of sidewalls defining corners between them. Each of the sidewalls is formed unitarily with a hinged strip which may be deflected inwardly and held in place therein by a snap-arrangement to support a similar container stacked thereon. When the strips are deflected outwardly, they allow the slightly tapered walls of the vessels to be interfitted or nested.

12 Claims, 9 Drawing Figures PATENTEUUCT 81974 'SHEEIBBF 3 FIG. 8

I, '1' III/I I II FIG. 9

STACKABLE TRANSPORT AND STORAGE CONTAINER SPECIFICATION I. Field of the Invention configuration and erected at the use site while the other remains generally intact from the point of manufacture to the point of use. While containers of the first type are easy to store and to transport until used, they are disadvantageous because of the efforts needed to erect the containers and place them in a structural staple form to receive the goods to be contained therein.

With containers of the second type, problems of stacking and transport are encountered, although erection costs are minimal. In recent years, with the ability of the synthetic-resin industry to turn out inexpensive large objects, thermoplastic injection-moldedv articles in the shape of upwardly open box-like containers have been produced for many purposes. These containers may be of the discardable or disposable type or reusable andmay be employed in the home, in industry and in agriculture.

The present invention is intended to deal with versatile stackable receptacles for such purposes. For the harvesting of orchard crops (fruits) and tender vegetables, the bushel basket has largely been replaced by rectangular upwardly open receptacles injectionmolded or otherwise formed from synthetic resin. Such containers are also used forthe transport of fish and other comestibles, may be employed in industrial plants for the movement of screw-machine products and other small objects, and may be used between a source of goods and the ultimate consumer, between a source of goods anda marketing site, between departments of a goods producer etc. Since large numbers of such containers may be required, they commonly are provided with a slight upward divergent or downward taper so.

that the outline of the base of each container lies within the outline ofthe top thereof, the walls sloping inwardly from the top to the bottom. This allows the containers to be nested before use.

However, it is frequently required that the containers be stacked in a partially or completely filled state in such manner as to hold the load of any superposed container off the goods in any lower container. This is particularly important where the goods are sensitive to compression or bruising as is the case with fruits and vegetables.

There have been proposed systems in which the walls of such containers are hinged to allow the container to be flattened for transport and storage and to be erected subsequently whereby the base of the container registers with the top of the next lower container so that force transmission or load transmission takes place through the container walls. This system has the disadvantages of earlier arrangements requiring complex erection procedures and has generally proved too expensive for the purposes described. In another arrangement, the walls, bottom and rim of the container are formed unitarily from a synthetic resin and the container is asymmetrical so that in one positionof the container, it may be nested with an underlying and/or overlying container while, in a position in which the container is swung through shoulders of the upper or lower container rest upon ledges of the other. The latter system has the disadvantage that it is not always possible to swing the container around through 180 before stacking and that manipulation of the containers is difficult. Moreover, these containers have not proved to be capable of economically withstanding high loads.

OBJECTS OF THE INVENTION be stacked without difficulty.

Another object of the invention is to provide a container structure which allows nesting of large numbers of containers as well as the stacking of the containers in force-transmitting relationship whereby the nested contains occupy little space and can be brought into stacked relationship without major reorientation of the container.

SUMMARY OF THE INVENTION These objects and others which will become apparent hereinafter are attained, in accordance with the present invention, with an upwardly open slightly taperd container, preferably having a rectangular plan configuration and-composes of a thermoplastic synthetic resin such, as polystyrene, polypropylene or polyethylene,

.which is formed at at least two and preferably three spaced-apart locations around the container with inwardly deflectable strips hinged to the walls of the container about generally upright axes and which normallly are generally coplanar with thewall for nesting of the containers but can be deflected inwardly into the path of the bottom of a similar container to be stacked thereon. Thes strips, which form support members or pedestals for the containers stacked thereon, preferably can be retained in their inwardly deflected positions by a snap-action arrangement either in the form of a detent or by providing the strip as part of a toggle or like arrangement movable past a dead-center position. The strip may thus have two operative positions on either side of the dead-center position or on either side of the detent, the first being an outer position in which the strip is coplanar with its wall to allow the containers to be nested while, in the second, the strip is inwardly deflected to allow it to support an overlying container.

I have used the term strip to refer herein to the bottom of an overlying container may rest. Preferably these pedestals are formed unitarily with the walls to which they are attached by a hinged web, the latter being a so-called hinge-foil and representing a portion of the wall or reduced thickness formed during the compression molding, casting or injection-molding process in which the container is formed from the synthetic resin. The hinge thus is also unitarily and mono- Iithically part of the wall structure, the walls being unitarily and monolithically formed with the upper rim of the container and the continuous and preferably planar floor thereof. An important point of the present invention is that the pedestal strip occupies a minor fraction of the length of the wall in the horizontal direction, whether this wall extends over the long leg or the short leg of the rectangle. Furthermore, the hinge web extends transversely to the length of the wall, i.e, in the vertical direction when the container is stood with its bottom upon a horizontal surface and thus the hinge axis lies generally perpendicular to the bottom of the container. When I refer to a slightly tapered construction of the container, I mean that the rectangular plane or outline of the bottom of each container lies within the rectangular outline of the top or rim thereof so that the end walls and lateral wall are inclined inwardly from the rim to the bottom. This allows the containers to be nested. Furthermore the containers are preferably mirror-symmetrical about the longitudinal and transverse median planes through the container.

According to a more specific feature of the invention, the strips or pedestals define the corners of the container and are constituted by at least two hingedly interconnected and unitarily formed strips, each belonging to one of the walls and hinged thereto. The interconnected strip may define an outer corner of the container in the outer positions of the strips but can be deflected inwardly to provide a generally triangular pedestal reaching inwardly to support the overlying container. Of course each strip may also be subdivided into hingedly interconnected strips to facilitate deflecting the pedestal inwardly past a dead-center position. The pedestal may thus have three or five hinges. As indicated, the pedestals may be provided at at least two locations, c.g., in diagonally opposite relationship although at least three pedestals are preferred, e.g., at three corners of the container. In the more common case, four pedestals will be provided although only three need be brought into play.

It should be noted that, to transform the container from a nesting receptacle into a stacking receptacle, it is merely necessary to deflect the corner pedestals inwardly to receive the overlying container, this being done by hand or automatically in a packing machine or the like.

In another embodiment of the invention, the strips are provided at the corners of the container although they are not hingedly interconnected. However, detents in the form of pins, knubs or the like may be provided across which the strips may be resiliently displaced to retain the two-leg pedestals at each corner in place. The strips need not extend over the full height of the container or its undisturbed storage compartment although it is preferred that the pedestals rest in force-transmitting relationship with the bottom of the container. Where the pedestals do not run the full height of the undisturbed-storage compartment, they may be of triangular configuration and form acute angles with the respective walls or hinges to transfer force to the latter.

DESCRIPTION OF THE DRAWING The above and other objects, features and advantages of the present invention will become more readily apparent from the following description, reference being mde to the accompanying drawing in which:

FIG. 1 is a perspective view of a transport container having four snap-action pedestals according to the invention;

FIG. 2 is a cross-sectional view taken along line II II of FIG. 1 showing the pedestal strips in their positions in which the container is nestable;

FIG. 3 is a cross-section taken along the line III III of FIG. 1 showing the pedestal in a position in which it is adapted to support the load of a similar container stacked thereon;

FIG. 4 is a cross-sectional view generally similar to FIG. 3 but showing a different pedestal structure;

FIG. 5 is a section similar to FIG. 2 through a pedestal arrangement using detents;

FIG. 6 is a view taken in the direction of the arrow VI of FIG. 5;

FIG. 7 is a view similar to FIG. 6 but showing another configuration of the pedestal-forming strips;

FIG. 8 is a vertical section through a pair of nested containers according to the invention; and.

FIG. 9 is a similar section (showing the upper container in elevation) of an arrangement in which the containers are stacked.

SPECIFIC DESCRIPTION Referring first to FIGS. 8 and 9 from which the operating states of a container according to the invention will be apparent, it should be noted that the basic container structure comprises a floor or bottom 40 whose width in rectangular plan view is represented at W, the container being formed unitarily with the vertical walls 41 and 42 which are tapered by an angle a of several degrees. The corresponding inner dimension W of the outwardly turned rim 43 of the container is greater than W toaccommodate the taper. It should be apparent that this structure allows the container C, to nest within the container C if the end walls are similarly tapered. The containers are identical and are formed along their walls with ribs 44 which project inwardly to define channels 45 facing the exterior of the container. Since the channels 45 extend downwardly and merge with the floor 40, the channel of an underlying container can receive the reinforcing rib 44 of an overlying container in the nested condition (FIG. 8) and for this purpose a draft is imparted to the walls of the ribs. The latter are described in greater detail in connection with FIGS. 1 7. The corners of the containers C, and C may be provided with inwardly deflectable pedestals 46, the upper edges 47 of which are separated by a distance D which is less than W and lie within the outline of the bottom 40 so that they are able to support the overlying container. The tops of these pedestals thus define a compressionfree compartment K in which goods may be received without compaction or compression by an overlying container. The corner pedestals may be provided as described in connection with FIGS. 1 7. To use the system of FIGS. 8 and 9, one merely withdraws one of the nested containers C, from the other C,,, deflects the corner pedestals inwardly, and places the upper container C, upon the lower.

Suitable containers for use as described in connection with FIGS. 8 and 9 can be provided as shown in FIG. 1. The upwardly open box-like container 1 of this Figure is composed of injection-molded synthetic resin with a monolithic structure including a bottom or floor 2, sidewalls 3 6, reinforcing vertical ribs 7 (which also define channels as noted earlier) and a peripheral outwardly turned flange or rim 8. Members 2 8 thus are composed as a single piece.

At the corners 9 and 10 between the walls, I provide snap-hinges (which are shown in enlarged scale in FIGS. 2 and 3. Each snap-hinge comprises a pair of pedestal strips 12 and 13 interconnected by a flexible ligature of synthetic resin 14 forming the actual hinge piece and constituting 'a synthetic-resin foil or film which is sufficiently flexible as to accommodate the dis placement of the hinge represented in FIGS. 2 and 3. The pedestal pieces 12 and 13 are connected by respective flexible ligatures 15 with the respective sidewalls 3, 4 and 3, 6 respectively. The ligatures thus are synthetic-resin strips substantially thinner than the walls and extending along the so-called hinge axes substantially perpendicular to the bottom 2. Of course I may form the hinges separately, in which case members 12 and 13 may be connected with separately produced foils adhesively bonded to the sidewalls.

The container of FIG. lis mirror-symmetrical about a transverse median plane M, and the longitudinal median plane M In FIGS. 2 and 3, I show a snap-action hinge wherein the pedestal strips 12 and 13 are generally coplanar with the walls 3 and 4 in their outer or nonsupporting positions and have a total length L, L which exceeds the normal distance L between the hinges 15. The diagonal connecting the hinges l5 and represented at T in FIG. 3, is a dead-center position through which the pedestal is displaced. If the hinges 14, 15 are sufficiently thin and the thermoplastic material sufficiently elastic to accommodate this movement without rupture of the hinges, no special precautions must be taken. In some cases, however, it will be necessary, immediately after injection-molding of the container, to press the pedestals inwardly (FIG. 3) to provide flexibility and elasticity in the finished body.

In the position of the hinge 11 shown in FIG. 2, members l2 and 13 form the corner (corner 10 in FIG. 1) and lie outside the outline of the bottom 2. The containers may be thus nested one within another. In the arrangement shown in FIG. 3, however, the pedestals ll lie within the outline of the bottom of the container so that the bottom of an overlying container may rest thereon. The strips 12 and 13 may have a length S equal to the height K of the storage compartment if force transmission from container bottom to container bottom through the pedestals directly is required. However, the system of FIG. 6 may also be employed.

In FIG. 4 I show a system in which the hinge 16 is provided with four strips 17, l8, 19, 20 interconnected by ligatures 21 and joined by the latter to the sidewalls 22 and 23. Here again the total length of the sidewalls is greater than the distance between the wall hinges so that the strips are deflected past a dead-center position.

Another arrangement is shown in FIGS. 5 and 6 wherein detents 30 in the form of studs, pins and knubs project upwardly from the bottom 31 ofthe container at the corner. The pedestal strips 25 and 26 are respectively hinged to the walls 27 and 28 but are not connected together so that they may be swung inwardly individually as shown in broken lines through In this position, they are held against self return by the studs 30 which are arranged at the corners of a diamond. The other integrally molded studs 30 yieldably retain the members 25 and 26 against inward displacement. Since the strips 25 and 26 are deflectable, only slight pressure is necessary to overcome the resistance of the studs in displacing the pedestal strips inwardly and outwardly.

In the system of FIG. 5, moreover, only a single strip may be required to constitute the pedestal at each corner and itv should be evident that the studs may be provided along the upper rib of the container. It is also possible as shown in FIG. 7 to provide the studs on the underside of an overlying container 34, i.e., at the bottom 33 thereof as shown at 32. The strips are here swung inwardly and the upper container lowered in place. The strip 35 will, of course, swing out into coplanarity with its wall under the elasticity of hing 37 of the lower container when the upper oneis removed. In this embodiment, moreover, the pedestal strip 35 has a generally triangular configuration and the load forces are applied to the wall of the container in the direction of the vector V.

The improvement described and illustraed is believed to admit of many modifications within the ability of persons skilled in the art, all such modifications being considered within the spirit and scope of the invention except as limited by the appended claims.

I claim:

1. A transport and storage container for nestling with like containers and for the stacking of like containers thereon, the container comprising a bottom and a plurality of walls in slight tapered fixed relationship fixedly connected to said bottom, a plurality of pedestals hinged to at least some of said walls and deflectable from a position in which each pedestal lies outside the horizontal outline of the container into a position wherein the pedestal projects into the outline to support a similar container stacked thereon, said walls, said bottom and said pedestals being unitarily formed from synthetic resin and said pedestals being provided at least at two diagonally opposite corners of the container, said container having a rectangular plan configuration, said pedestals each comprising at least one strip unitarily hinged to a respective wall by a thin vertical web of the synthetic resin and deflectable from a position in which the strip is generally coplanar and flush with its respective wall into a position wherein said strip extends generally transversely to its respective wall, said strips extending vertically, said walls having recesses accommodating said strips in the firstmentioned position, and meansfor releasably retaining each strip in its last-mentioned position.

2. The container defined in claim 1 wherein said means for retaining said strip in its last-mentioned position comprises a stud crossed by the respective strip upon its displacement from one of its positions to the other of its positions with relative deflection of the strip and stud whereby said stud thereafter intercepts said strip.

3. The container defined in claim 2 wherein said studs are provided on said bottom for engagement with the strips of a container stacked therebelow.

4. The container defined in claim 2 wherein said studs are provided on the bottom of the container carrying the strip engaged by said studs.

5. The container defined in claim 1, further comprising means for retaining each of said strips yieldably in the first-mentioned of its positions.

6. The container defined in claim 5 wherein the lastmentioned means includes studs engageable with said strips.

7. The container defined in claim 5 wherein each of said strips is hingedly connected to a further strip hinged to another wall at the respective corner, the strips at each corner being deflectable past dead-center for displacement between their positions.

8. The container defined in claim 7 wherein four such strips interconnected by three hinges and connected to said walls by a further pair of hinges is provided at each corner of the container.

9. The container defined in claim 1, wherein said strips extend substantially into contact with the bottom 8 t of the container for force transmission between the bottom of a container stacked thereon and the bottom of a container provided with the strip.

10. The container defined in claim 1 wherein said strips are of triangular configuration and have outer edges extending downwardly at acute angles to the respective hinge axis.

11. The container defined in claim 1 wherein each of said strips is shiftable between its positions with snapaction.

12. The container defined in claim 1, further comprising an outwardly turned rim extending all around said walls and formed unitarily therewith, a respective pedestal being provided at each of the corners of the container and supporting a container stacked thereon over a compression-free space, said walls being providedwith reinforcing ribs at spaced locations therealong. 

1. A transport and storage container for nestling with like containers and for the stacking of like containers thereon, the container comprising a bottom and a plurality of walls in slight tapered fixed relationship fixedly connected to said bottom, a plurality of pedestals hingeD to at least some of said walls and deflectable from a position in which each pedestal lies outside the horizontal outline of the container into a position wherein the pedestal projects into the outline to support a similar container stacked thereon, said walls, said bottom and said pedestals being unitarily formed from synthetic resin and said pedestals being provided at least at two diagonally opposite corners of the container, said container having a rectangular plan configuration, said pedestals each comprising at least one strip unitarily hinged to a respective wall by a thin vertical web of the synthetic resin and deflectable from a position in which the strip is generally coplanar and flush with its respective wall into a position wherein said strip extends generally transversely to its respective wall, said strips extending vertically, said walls having recesses accommodating said strips in the first-mentioned position, and means for releasably retaining each strip in its last-mentioned position.
 2. The container defined in claim 1 wherein said means for retaining said strip in its last-mentioned position comprises a stud crossed by the respective strip upon its displacement from one of its positions to the other of its positions with relative deflection of the strip and stud whereby said stud thereafter intercepts said strip.
 3. The container defined in claim 2 wherein said studs are provided on said bottom for engagement with the strips of a container stacked therebelow.
 4. The container defined in claim 2 wherein said studs are provided on the bottom of the container carrying the strip engaged by said studs.
 5. The container defined in claim 1, further comprising means for retaining each of said strips yieldably in the first-mentioned of its positions.
 6. The container defined in claim 5 wherein the last-mentioned means includes studs engageable with said strips.
 7. The container defined in claim 5 wherein each of said strips is hingedly connected to a further strip hinged to another wall at the respective corner, the strips at each corner being deflectable past dead-center for displacement between their positions.
 8. The container defined in claim 7 wherein four such strips interconnected by three hinges and connected to said walls by a further pair of hinges is provided at each corner of the container.
 9. The container defined in claim 1, wherein said strips extend substantially into contact with the bottom of the container for force transmission between the bottom of a container stacked thereon and the bottom of a container provided with the strip.
 10. The container defined in claim 1 wherein said strips are of triangular configuration and have outer edges extending downwardly at acute angles to the respective hinge axis.
 11. The container defined in claim 1 wherein each of said strips is shiftable between its positions with snap-action.
 12. The container defined in claim 1, further comprising an outwardly turned rim extending all around said walls and formed unitarily therewith, a respective pedestal being provided at each of the corners of the container and supporting a container stacked thereon over a compression-free space, said walls being provided with reinforcing ribs at spaced locations therealong. 